diff options
author | Patrick Steinhardt <ps@pks.im> | 2022-12-01 17:46:53 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2022-12-09 08:26:21 +0300 |
commit | 522cc87fdc25449222a5894a428eebf4b8d5eaa9 (patch) | |
tree | 05b0e6b3fc523e14d7eb612abe30520681313a26 /utf8.c | |
parent | 48050c42c73c28b0c001d63d11dffac7e116847b (diff) |
utf8: fix truncated string lengths in `utf8_strnwidth()`
The `utf8_strnwidth()` function accepts an optional string length as
input parameter. This parameter can either be set to `-1`, in which case
we call `strlen()` on the input. Or it can be set to a positive integer
that indicates a precomputed length, which callers typically compute by
calling `strlen()` at some point themselves.
The input parameter is an `int` though, whereas `strlen()` returns a
`size_t`. This can lead to implementation-defined behaviour though when
the `size_t` cannot be represented by the `int`. In the general case
though this leads to wrap-around and thus to negative string sizes,
which is sure enough to not lead to well-defined behaviour.
Fix this by accepting a `size_t` instead of an `int` as string length.
While this takes away the ability of callers to simply pass in `-1` as
string length, it really is trivial enough to convert them to instead
pass in `strlen()` instead.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'utf8.c')
-rw-r--r-- | utf8.c | 8 |
1 files changed, 3 insertions, 5 deletions
@@ -206,13 +206,11 @@ int utf8_width(const char **start, size_t *remainder_p) * string, assuming that the string is utf8. Returns strlen() instead * if the string does not look like a valid utf8 string. */ -int utf8_strnwidth(const char *string, int len, int skip_ansi) +int utf8_strnwidth(const char *string, size_t len, int skip_ansi) { int width = 0; const char *orig = string; - if (len == -1) - len = strlen(string); while (string && string < orig + len) { int skip; while (skip_ansi && @@ -225,7 +223,7 @@ int utf8_strnwidth(const char *string, int len, int skip_ansi) int utf8_strwidth(const char *string) { - return utf8_strnwidth(string, -1, 0); + return utf8_strnwidth(string, strlen(string), 0); } int is_utf8(const char *text) @@ -791,7 +789,7 @@ int skip_utf8_bom(char **text, size_t len) void strbuf_utf8_align(struct strbuf *buf, align_type position, unsigned int width, const char *s) { - int slen = strlen(s); + size_t slen = strlen(s); int display_len = utf8_strnwidth(s, slen, 0); int utf8_compensation = slen - display_len; |